Method of casting explosives



May 22, 1 928. 1,670,689

H. H. OLMSTEAD METHOD OF CASTING EXPLOSIVE S Filed Jan. 50, 1926 na wmw gin dew; a

I HENRY H. OLHSTEAD, OF WHARTON, NEW JERSEY.

METHOD OF CASTING EXPLOSWES.

Application filed January 80, 1826. Serial No. 85,027..

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The invention described herein may be used by the Government, or any of its officers or employees inprosecution of work for the Government, or by any other person in the United States, without payment to me of any royalty thereon, in accordance with the act of March 3, 1883.

This invention relates to a cast of explosive and method of forming the same.

In order to secure the best results and maximum power in a bomb, mine, or the like, the explosive must be packed mto the container or shell under a uniform high density.

The general procedure known as the breaking-down method which has been heretofore followed in loading bombs consists in pouring a' rather large amount of molten explosive at a temperature of 79 G. into the container, and after this has soliditied to add gradually reduced increments.

After each pouring a crust immediately forms upon the surface which retards the cooling of the semiliquid underneath. At frequent intervals this crust is broken down and the liquid stirred. As the liquid cools and solidifies cavities are formed in the center of the mass so that before the final increments are added it is necessary'to drill holes in the center of the casts to reach all of the cavities. According to this method, several days are required to load a small bomb containing 150 lbs. of explosive.

The principal object, then, of this invention is to provide an improved method of loading containers such as bombs with an explosive charge of uniform and maximum density in a short eriod of time. I have discovered that it is impossible to cast explosives to a greater thickness than one-half inch without cavities and a layer of lower density forming between the upper and lowerportions of the cast. To follow the above. rate of pouring in filling a container such as a bomb which is usually of a'depth of from 5 to 7 feet would require an inordinately great period of time and I therefore propose in the present invention to provide a large number of casts each formed externally of the container and comprising a laminated block, the layers of which are poured successively after stated cooling intervals .and are of a thickness of approximately one-half inch.

To these and other ends, my invention con- Fig. 4 is an enlarged fragmentary sec tional view through one of the staples provided for lowering the casts into the container.

Referring to the drawings by numerals of reference:

There is shown a bomb casing or shell 5 loaded with a plurality of laminated casts 6 of an explosive such as trinitrotoluene. The casts 6 may be of any desired thickness, preferably six inches, the controlling factors being convenience in loading and the relationdof the cooling period to the usual workm ay.

Ihe casts may be simultaneously formed in separate molds and the method'of forming them consists in pouring, at intervals of thirty minutes, measured amounts of molten explosive at a temperature of 7 9 G. into the mold forming layers 7--7, a half-inch in thickness. This allows a rapid cooling of the layers and insures uniform and maximum density without cavitation throughout each layer. The cooling period of each layer is sufiiciently short to permit twelve layers to be poured within the space of six hours so that one man tending to twentyfour molds every half hour-would be able during a working day to perform all tasks necessary to preparing the molds and removing the casts.

The casts are preferably formed with a convex bottom 8 and a concave top 9 to facilitate staking on loading them into the bomb and to insure centering.

Laminated casts formed according to my improved method possess ,considerable structural strength as it has been found in exposed less 'to stricted as at 12 so as to be more firmly gripped and are embedded sufliciently deep so as not to project above the concave upper face of the when placing them into position. In lowering the cast into the bomb casing or raising it therefrom a rope or hook may be conveniently engaged with the staples.

' This improved method .of loading bombs possesses a great advantage over the breaking-down method inthat the personnelare the absorption of, the explosive. K

Y I claim:

fapproximately one-half inch lock. Any suitable apparatus may be provided for holding the staples 1. A method of forming casts of explosives which consists in lpourin an amount of explosive into a mo (1 to Form a layer allowing it tocool for approximately thirty minutes, and successively adding and cool-v ing increments of the explosive to form layers of similar thickness.

2. A method of forming casts of explosives which consists in'pouring an amount of explosive into a mold to form a layer of approximately one-half inch in thickness, allowing it to cool, and successively adding and cooling increments of the explosive to 'form layers of similar thickness.

3. A method of forming casts of explosives which consists in pouring an amount of explosive into a mold to form a thin laver, allowing it to cool, and successively adding and cooling similar amounts of the explosive. v HENRY H. OLMSTEAD.

in thickness, 

